Sample code for 30+ languages & platforms
.NET Core C#

SMTP using SOCKS5, SOCKS4 Proxy

Demonstrates how to communicate with an SMTP server via a SOCKS4 or SOCKS5 proxy.

Chilkat .NET Core C# Downloads

.NET Core C#
bool success = false;

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// The mailman object is used for sending and receiving email.
Chilkat.MailMan mailman = new Chilkat.MailMan();

// To use a SOCKS4 or SOCKS5 proxy, simply set the following
// properties prior to making any calls that communicate with
// an SMTP server:
// The SOCKS hostname may be a domain name or 
// IP address:
mailman.SocksHostname = "www.mysocksproxyserver.com";
mailman.SocksPort = 1080;
mailman.SocksUsername = "myProxyLogin";
mailman.SocksPassword = "myProxyPassword";
// Set the SOCKS version to 4 or 5 based on the version
// of the SOCKS proxy server:
mailman.SocksVersion = 5;
// Note: SOCKS4 servers only support usernames without passwords.
// SOCKS5 servers support full login/password authentication.

// Set the SMTP server.
mailman.SmtpHost = "smtp.chilkatsoft.com";

// Set the SMTP login/password (if required)
mailman.SmtpUsername = "myUsername";
mailman.SmtpPassword = "myPassword";

// Create a new email object
Chilkat.Email email = new Chilkat.Email();

email.Subject = "This is a test";
email.Body = "This is a test";
email.From = "Chilkat Support <support@chilkatsoft.com>";
success = email.AddTo("Chilkat Admin","admin@chilkatsoft.com");

// Call SendEmail to connect to the SMTP server and send.
// The connection (i.e. session) to the SMTP server remains
// open so that subsequent SendEmail calls may use the
// same connection.  
success = mailman.SendEmail(email);
if (success != true) {
    Debug.WriteLine(mailman.LastErrorText);
    return;
}

// Some SMTP servers do not actually send the email until 
// the connection is closed.  In these cases, it is necessary to
// call CloseSmtpConnection for the mail to be  sent.  
// Most SMTP servers send the email immediately, and it is 
// not required to close the connection.  We'll close it here
// for the example:
success = mailman.CloseSmtpConnection();
if (success != true) {
    Debug.WriteLine("Connection to SMTP server not closed cleanly.");
}

Debug.WriteLine("Mail Sent!");